Feeding mechanism for sewing machines



Janis 1926.

A. H. DE voE FEEDING MECHANISM FOR SEWING IIACHINES 4 Sheets-Sheet 1 A/ber/ liar/6Q BY W ATTORNEY Filed Oct. 14, 1922 WIT ass? Jan. 5 1926. 1,568,399

A. H. DE VOE "5mm xncnmzsu FOR snwme mcnnms Filed Oct. 14, 1922 4 Sheets-Sheet 2 INVENTOR wlmzsg} A/b r/ A 0e Voe I BY ATTORNEY Jan. 5 1926.

A. H. DE VOE FEEDING mncmmzsu FOR SE'WING MACHINES Filed Oct. 14, 1922 4 Sheets-Shet' '5 w p r j 1 M v mm m x A :L w MM A N m WW- m w J m 2 WITNESS I A r Patented Jan. 5, 1926.

. UNITED STATES PATENT OFFICE.

ALBERT H. DE VOE, OF WESTFIELD, NEW JERSEY. ASSIG-NOR TO THE sl'NG -ER MANU- FACTURING COMPANY, OF ELIZABETH, NEW JERSEY, A CORPORATION OF NEW JERSEY.

FEEDING MECHANISM FOR SEWING MACHINES.

Application filed October 14, 1922. Serial No. 594,447.

1 0 all to 710m it may concern Be it known that I, ALBERT H. Dn Von, a citizen of the United States, residing at Vestlield, in the county of Union and State of New Jersey, have invented certain new and useful Improvements .in Feeding Mechanismsfor Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings. This invention relates to improvements in sewing machine feeding mechanisms, and while it is more particularly designed for embodiment in sewing machines fitted for stitching together the soles and uppers of Japanese tabis. certain features thereof are equally capable of being incorporated in sewing machines adapted for general use.

The invention has for one of its principal objects to increase the speed and efficiency of sewing machines by the provision of improved supporting and actuating means for a four-motion upper feeddog.

It has a for a further object to provide improved means for actuating and controlling an auxiliary feeding mechanism to produce different rates of advance of superposed plies of flexible cloth comprising the uppers of Japanese tabis relative to each other and to the sole to compensate for the different lengths of such fabric plies used in the alternate gradual and abrupt corrugations or bends of the material.

In its preferred form, the four-motion upper feed-dog is carried by a feed-bar so connected with a vibratory feed-lift arm that the feed-dog is yieldingly pressed upon the work by a spring during the work-advancing movements thereof, but is positively lifted from the work and returned to initial position without opposition by'said spring, thereby relieving the operating mechanism from compressing the spring'during approximately three-fourths of a complete movement of the feed-dog.

The clan'iping jaws comprising the auxiliary or differential feeding mechanism receive their workadvancing and return movements from a cam-actuated vibratory arm operating in opposition to a spring which acts to return the clamping-jaws to an initial position. This initial position may be fixed by a predetermined adjust ment ofthe degree of lost motion permitted between the vibratory arm and a clampingja-w carrier, and which position may be varying automatically through a complete operation by the action of a limit-determining cam receiving step-by-step advancing movements through a gear connection with a ratchet wheel. This ratchet wheel may be rotated in opposite directions by either one of two reciprocated pawls selective at will, which pawls can both be maintained ininefiective positions in the constant retracted position of the jaws.

In the accompanying drawings, Fig. 1 is a front'side elevation, partly in section, of a tabi-stitching machine embodying the present improvements. Fig. 2 isa rear side elevation, partly in section, of the same. Fig. 3 is a sectional view substantially ou the line aa;, of Fig. 2. Fig. 4 is a sectional view substantially on the line 1 of Fig. 2. Fig. 5 is a detail view of the yielding connection between the primary feed-lift rock-shaft and the auxiliary feed pull-rod. Fig. 6 is a plan view of the bedplate and auxiliary feeding device. Fig. 7 is an end elevation of the head of the bracket-arm, illustrating the primary feeddog and its support. Fig 8 is a perspective view of the abutment-cam actuating pawls.

The present invention comprises an 1111-.

provement of the tabi-stitching machine illustrated in my Patent No. 1,191,068, of July 11, 1.916, to which reference may be had for an understanding of the general construction and operation of the parts not completely disclosed herein.

The frame comprises the bed-plate 1 and hollow bracket-arm composed of the hollow standard 2 and overhanging tubular member 8, terminating at its forward end inthe head 4- in which is journaled the reciprocating needle-bar 5 carrying the needle 6. The needle 6 may cooperate with any suitable form of complemental stitch-forming mechanism and therefore no further refer ence is herein made thereto. The main-shaft 7 journaled in the bracket-arm member 3 carries the combined balance-wheel andbeltpulley 8.

The primary feeding-member comprises a swinging feed-bar 9 to the lower end of which is secured by screws, as 10, the shank of a four-motion-upper feed-dog 11 divided centrally bythe needle-aperture or notch 12 and provided with work-engaging spurs, as

13, spaced in the direction: of feed. The feed-bar 9 has a yielding pin-and-slot connection with feed-lifting means constituting a yielding pivotal support for the feedbar, and to this end the upper end of the feed-bar is bent to form a loop or hook 14 straddling a fulcrum and lifting pin 15, between spaced ears provided at the free end of a vibratory arm 16. The arm 16 is fixed upon the forward end of a primary feed-lift rock-shaft 17, journaled in suitable lugs 18 provided on the rear side of the bracket-arm 8 and to which is clamped the split hub of a crank-arm 19 carrying a roller-stud 20 which enters the cam-groove 21 formed in the rearward face of a cam 22 suitably secured .upon the main-shaft 7. Interposed between a collar 23 adjustably secured upon the feed-bar 9 and a washer 24 bearing against the lift-arm 16 is a coiled spring surrounding the feed-bar and urging the latter in the direction of the throatplate 26 havin the usual needle-aperture 27. That is, the tendency of the spring is to seat the upper end of the feed-bar upon the pin 15 and when so seated, the feed-bar and spring are lifted as a unit by the upward movements of the arm 16. These parts are adjusted so that the feed-dog 11 engages the work before the arm 16 has. completed its downward movement, thereby creating a clearance between the loop 14 and the pin 15 and leaving the feed-bar during its workadvancing movements solely under the pressure of the spring 25. Consequently the initial upward movement of'the arm 16 is aided by the spring 25 by reason of the feed-dog bearing upon the work and therc after no force is consumed in further or again compressing the spring until the feeddog again contacts with the work after its return movement.

In order to impart work-adrancing and return movements to the feed-dog, the feed bar 9, which i rectangular in cross-section at its lower end, is slidingly guided by a similarly apertured block 28 provided with an elongated transverse slot 29 entered by a, headed pin 30 secured by means a setscrew 31 in'the free end of a vibratory arm 32 depending from a feed-shaft The rearward end of the slot 29 is normally maintained in contact with the pin. 30 by a. spring 34 carried by the arm 32 and bearinn: against the block 28. This constructi n permits of increasing the length of stitch being. formed. when desired. by a pulling action upon the work rearward of the feed-dog. The feed-shaft 33 is suitably iournaled in the machine. frame and has lied to its rearward end a segment 35pmded with an arcuate slot 36 in which a slidelock 37, pivotallv carried by one end of alink 38.. is adjustablv secured by means of a clamp-lever 39. The opposite end of the link 38 is pivotally connected, by pivotbolt 40, with a triangular crank 41 having a hub 42 loosely journaled upon the primary feed-lift rock-shaft 17. Also carried by the crank 41 is a roller-stud 44 entering a camgroove 45 in the forward face of the cam 22, which cam therefore also serves to impart the feeding and return movements to the primary feed-dog.

The auxiliary feed-clamp herein disclosed is constructed substantially in accordance with that illustrated in my prior patent before referred to and operates in the same manner for the same purpose. Improved actuating and controlling connections are however providedfor this feed-clamp, which latter comprises a vibratory carrier-lever 46 having a tubular hub 47 mounted in a hearing boss 48 depending from the bed-plate l. Journaled in the hub 47 is the depending fulcrum-pin 49 of the block 50 channeled in its lower face to receive the arm 51 provided with the lower work-clamping jaw 52. An upper clamping jaw 53 is formed upon the downwardly offset forward end of the arm 54 fulcrumed for edgewise movement upon the stud-screw carried by the rocking support 56 which is in turn pivotally mounted upon the transverse pin 57 on the block 50. Tnterposed between the block 50 and the arm or lever is the spring 58 which norn'ially acts to separate the work engaging jaws and a steady pin 59 fixed upon the lower jaw projecting through an aperture 60 in the upper jaw, thereby limiting the lateral movement of the upper jaw upon the fulcrum-stud The width of the aperture 60 affords sufficient clearance for a slight lateral movement of the upper jaw relatively to the steady-pin 59.

"rdjustably secured upon the rearward portion of the arm or lever by means of screws 61 and 62, is the Contact plate 68 having. an extension 64 whose forward edge and lower face normally rest in contact with stop-shoulders provided upon a block 65 secured by screws .66 upon a pull-rod 67 journaled at its lower end for vertical movement in the bed-plate 1. The extension 64 is normally maintained in engagement with stop-shoulder of the block 65 by means of a spring 68 interposed between :1 depending lip 69 of said plate 63 and the, adjacent edge of the rocking support 56. v

The pull-rod 67 is pivotally connected at its upper end with the arm 70 projecting forwardly from a sleeve 71. loosely jour naled upon the feed-shaft 33 and provided with an upwardly extending crank-arm 72. The arm 72 carries a stud 73 embraced by a strap 74 at. one end of the push-rod 7 5 which passes loosely through an eye formed in a rocking stud 76 carried by the crankarm 77 fixed upon the feed-lift rock-shaft 17. A spring 78, stronger than the spring 58,

is interposed between the stud 76 and a nut 79 threaded upon the push-rod, said spring 78 serving to normally maintain the actuating parts in relatively fixed relationship, whereby the rocking movements of the shaft 17 will not only impart lifting movements to the feed-dog 11 but will transmit its movements through the push-rod to the pull-rod 67, whereby the auxiliary clamp is alternately opened and closed by the downward movement of the block 65, permitting the spring 58 to open the jaws, and by the upward action of the block 65 upon the extension 64 to close the same.

The spring 78 is however adapted to yield when the primary feed-dog 11 is manually lifted and the clamp-jaws are opened for insertion and removal of the work. In order to effect this lifting action, a rocking sleeve 80 is loosely journaled upon the feed-shaft Fixed to oscillate with this sleeve 80 is a hand-operated lever 81. projecting forwardly underneath the overhanging bracketarm and under the action of a spring 82 which normally holds the forward end of said lever 81 in raised position. The lever 81 is provided with a lateralextension 83 terminating in an apertured ear 84 journaled upon the outer end of the feed-shaft 33 projecting' beyond the head 4. the additional journaling affording a firmer bearing for said lever. The ear 8 1 carries a roller-stud 85 adapted to engage a cam-plate 86 secured by screws, as 87, upon the lift-plate 88, provided with guide-slots 89 and 90. The

guideslot 89 coacts with a screw 91 threaded into the machine head and the slot with the end of the feed-shaft for the pur pose of confining the lift-plate 88 to vertical movements. The lowerend of the lift-plate carries a roller 92- adapted to engage a lug on a collar 93 secured by means of a screw 94 upon the feed-bar 9. It is evident that upon manual depression of the forward end of the lever 81 against the action of the spring 82, the roller-stud 85 acts to lift the plate 88 and through the action of the roller 92lift the feed-bar 9 and the feeddog carried thereby. The return upward movement of the lever 81 under the action of the spring 82 is limited by its contact with the overhanging bracket-arm. The teed-dog 11 reaches its upward limit of movement under the action of the lever 81 when the roller-stud 85 contacts with the low-point 86 on the cam-plate 86. A further movement of the lever 81 is, however. permitted by the subsequent movement of the stud 85 beyond the low-point 86. As the stud-'85 is now approaching the highest point in its orbit of movement. the feed-dog 11 is maintained in its raised position. The

additional movement of the lever 81 serves to open the clamp-jaws of the auxiliary feed in the following manner. The rocking sleeve 80 which oscillates with the lever 81 is provided at its rearward end with a shoulder 95 disposed in the path of movement of a rib 96 formed on the arm 70, which controls the opening and closing of the workclaniping jaws. In the normal operative position, suiiicient clearance is provided be tween the shoulder 95 and the rib 96 to prevent coaction therebetween until after the teed-dog 11 has reached the described upper limit of movement by depression of the hand-lever 81. Further movement of this lever serves to depress the pull-rod 67, thereby permitting the spring 58 to open the aws, while in the return movement the block 65 acts upon the extension 64. to close the jaws. This movement of the arm 70 is permitted by the provision of the buffer-spring 78. From the foregoing it is apparent that during the operation of the machine the feeddo; 11 is raised and lowered simultaneously with the opening and closing of the workclz'imping jaws 52 and but thatupon manual manipulation of the lever, said jaws are opened after the feed-dog 11 is lifted and closed before said dog is lowered.

The block 50 is formed with the forwardly projecting arm 97 terminating in a segmental cam-edge 98 formed with the wedgeshaped notch 99 entered by the correspondingly shaped tooth 1.00 of a latch-bar 101 spring-pressed into latching relationship. Pivotally mounted upon the block 50 is the release lever 102 adapted to engage the latchbar 101 for disengaging the tooth from the notch 99 to permit the auxiliary workteeding members to he pivotally swung from operative position in which the jaws and 53 are disposed in advance of the needle.

Projecting from the carrier-lever 16 is a hardened contact-pin 103 adapted to be engaged by a wear-block 104 fixed upon the free end of a depending arm 105, the hub of which is clamped by means of screwsas 106, upon. a short shaft 10'? suitably journaled in the machine-frame. Secured upon the shaft-107 is a crank-arm 108 carrying a T0116!- stud 109 entering a can'i-groove 110 of a cam 111 fixed upon the mainshaft 7. The vibratory movements thus transmitted to the arm by the cam 111 causes said wearblock 10 1 to engage the contact-pin 103 to oscillate the clamping-jaws 52 and 53, while clamping the work therebetween, toward the primary feed-dog 11. The return movement of the jaws is effected by a spring 112, coiled about a stud 113 fixed upon the arm 105 and entering an aperture in the lever 46.

The effective action of said arm 105 is controlled by limiting the return movement of the lever 46, under the action of the spring 112, and thus creating lost motion between the arm 105 and said lever 46. This lostmotion may be constant to produce a predetermined falling or gathering action upon the upper, or it may vary automatically to produce a varying degree of fulling according to the adjustment of the parts about to be described.

The carrier-lever 46 is provided with an upstanding ear 114 into which are threaded two adjusting screws 115 and 116 adapted to be locked in adjusted positions by locinuts as 117. Loosely journaled upon a bearing stud 118 secured in an aperture in the standard 2 is a spur-gear 119 carrying a. cam in fixed relation therewith. This cam has a concentric periphery 126 terminating in a cam-surface 121 projecting laterally be yond a flat web 122. The cam-surface. 121 constitutes a variable abutment for the adjusting screw 115 to limit the return movement of the lever 46 and the web 122 comprises a constant abutment for the screw 116, it being understood that the screws 115 and 116 are so adjusted that one is ineifective in the operative position of the other. The spur-gear 119 meshes with a pinion 123 loosely journaled upon a stud-screw 124 threaded into the standard 2. Also loosely journaled upon the stud-screw 124 are a ratchet-wheel 125 and a manipulating knob 126, which are both pinned to the pinion 123 to rotate therewith. A spring 127 is interposed between the head of the stud-screw 124 and a flange 128 upon the knob 126 whereby the parts are maintained in operative relationship and whereby overthrow is prevented. By manipulating the knob 126, the pinion 123 may be rotated'in either direction, which causes a corresponding rotation of the gear 119 to obtain an initial position of the cam-surface 121 with respect to the stop-screw 115 in the effective position of the latter. This initial position may be determined by means of an index finger 129 secured upon the bearing-stud 118 by means of a screw 130.

During the operation of the machine. the cam 121 may be rotated by means of either one of two pawls 131 and 132 pivotally supported upon fulcrum-screws, as 133, thread ed into a carrier-block 134 secured upon the forward end of an oscillating member 135. The member 135 is provided with spaced apertured ears 136 loosely journaled upon the feed-shaft 33 on opposite sides of the hub of the segment 35, said member having an upwardly projecting arm 137 carrying a cam-roller 138 entering the feed-actuating cam-groove 45 at a point substantially dia metrically opposite to the point of contact of the roller-stud 44 with said cam-groove. The member 135 has a depending lug 139 carrying a guide-roller 140 tracking a guideway 141 provided in the standard 2.

The pawls 131 and 132 have lateral extensions 142 and 143 each formed with a seg mental depression, as 144, terminating in stop shoulders, as 145. Positioned to coact with the depressions 144 is the periphery of a disk 146 provided with a segment-notch 147 adapted to alternately engage the stopsh'oulders 145, while the extensions 142 and 143 are each yieldingly pressed upwardly by a spring 148 seated in apertured lugs 149 provided on the carrier-block 134. The disk 116 is carried by a spindle 150, journaled in a suitably apertured boss 151 on the carrierblock 134 and carrying a pawl-manipulating finger 152. In the central position of the finger 152, both of the pawl-extensions 142 and 143 are held depressed by the disk 146 against the action of the springs 148, but in either the right or lefthand position of the linger 152, the disk 146 maintains one of the pawl-extensions depressed and permits the other to yield upwardly until the stopshoulder engages a wall of the segment notch 147. Consequently either one of the pawls 131 and 132 may be thrown into operative engagement with the ratchet-wheel 125. whereupon the oscillations of the member 135 are transmitted to the cam 121. to rotate the latter in the desired direction.

hen it is desired to effect a return movement of the clamping jaws 52 and 53 to a predetermined position throughout the operation of the machine the screw 115 is retracted out of engagement with the cam 121 and the screw 116 adjusted into the desired position of engagement with the web 122. To avoid unnecessary sliding wear upon the web 122, the finger 152 may be thrown into central or neutral position whereupon the cam 121 ceases to be rotated.

In the use of the machine as thus described, the primary feed-dog 11 and the upper clamping-jaw .3 are first successively lifted by manipulation of the lever 81, and the tabi-sole placed upon the throat-plate below the lower jaw 52 and the feedingfoot 11. The superposed plies of material comprising the upper are then introduced between the jaws 52 and 53 and below the feed-dog 11, after which the previously lifted members are lowered into engagement with the work. When it is desired to automatically control the auxiliary feeding jaws 52 and 53 to progressively vary their fulling action, the stop-screw 115 is adjusted the desired extent to engage the cam 121 and the stop-screw 116 released, While the finger 152 is thrown into either right or left hand position according to the nature of the operatlon.

The machine is now set in motion, whereupon the particular pawl in action imparts a step-by-step advancing movement to the cam 121 thereby constantly varying the retracted position of the auxiliary feeding jaws and consequently their amplitude of feeding movement. As the jaws 52 and 53 approach the limit of each of their work-advancing movements, the upper jaw 53 is retarded by the extension 64 abutting against the shouldered block 65, as in the machine of my prior Patent No. 1,191,068 and for the pur' pose of effecting a relative movement of the plies of fabric com rising the upper. The auxiliary feeding evice forces the upperfabric against the forward face of the primary teed-dog 11, in which condition it is secured to the sole by the descent o the needlc. lhe feed-dog ll and the upper clampjaw 53 are now n'iechanically lifted and returned to initial position, the spaced spurs 1o straddling the tolled portions of the tabric, whereupon the needle rises followed by worlpadvancing movements of the feeding devices.

Having thus set forth the nature of the invention, what I claim herein is 1. A tour-motion upper feeding mechanism for sewing machines comprising a feedlift rock-arm tulcrumed upon the machine frame, means for actuating said arm, a feed bar, a yielding pivotal support for said feedbar upon said arm, a teed-dog on said teedbar, means for imparting work-feeding movements to said teed-bar, and a spring interposed between said arm and said feed be r and acting by its resilience throughout the work-feeding movements 01 said feed- (log to yieldingly maintain the feed-dog in engagement with the work. i

A fourmotionupper feeding mechanism. for sewing machines, comprising a teed-bar, a feed-dog carried thereby, a vibratory feed-lift arm, a pin-and-slot connection between said element and said arm, a spring interposed between said arm and said iced-bar, means for vibrating said arm, and operative connections for imparting workadvancing movements to said teed-dog including a connection yielding in the direction of feed.

3.1-8. tour-motion-upper feeding mechanism for sewing machines, comprising a feed-bar, a teed-dog carried thereby, a vibratory feed-lift arm, a pin-and-slot connection between said arm and said teed-bar permitting vertical movement of said feed-bar independently of said f'eed-lift-arm, a spring interposed between said arm and said feed bar acting by its resilience throughout the worlnteeding movements of said teed-dog to yieldingly maintain the teed-dog in engagement with the worlc, means for vibrating said arm, means for imparting work-advancing movements to said feed-dog, and manually operated means for lifting said feeddog in opposition to said spring.

4. A four-motion-upper feeding mechanism for sewing machines, comprising a teed-dog, a spring yieldingly urging said teed-dog to engage the work, operative connections for imparting work-advancing movements to said teed-dog, mechanically operated means unopposed by said spring for lifting said teed-dog above the work, and manually operated means for lifting said teed-dog in opposition to said spring.

5. A tour-motion-upper feeding mechanism for sewing machines, comprising a teed-bar, a teed-dog carried thereby, vibratory feed and feed-lift elements, an operative connection between said teed-bar and the vibratory teedelement yielding in the dir ction of teed-movement of said feed-dog, and an operative connection between said 'i eed bar and the vibratory teed-lift element to permit relative yielding movements thercbetvveen in a direction substantially at right angh to the plane or the work.

(l. The mmbination in a sewing machine including a bed-plate and an overhanging arm, of an upper 'i eeding mechanisn'i comprising a teed-bar, a teed-dog carried by said teed-bar a feed-lift rock-shaft, means for acti'iting' said roclnshai t, a vibratory arm carried by said roclnshait, a yielding connection between the vibratory arm and said feed-bar, a spring opposing relative yielding movement between said arm and said bar in the work-engaging movement of said teed-dog, means for imparting feeding movements to said t'eed bar, a manually manipulated litter-lever fulcrumed upon said rock-shaft and extending forwardly underneath said overhanging arm, and an operaive connection between said lever and said teed-bar to raise said feed-dog above the work in opposition to the action of said sprin I T. In a sewingmachine, the combination with primary and secondary feeding members, and operative connections for imparting to said members differential work-advancing moven'ients, of a teed-lift rock-shaft, a yielding connection between said rockshat't and said primary work-feeding member, a yielding connection between said rockshaft and the secondary work-feeding member whereby the latter is moved into and out of engagement with the work, a manuall manipulated litter-lever fulcrumed upon said rock-shaft, and diiierentially timed connections between said lifter-lever and the primary and secondary work-engaging members.

8. In a sewing machine, the combination with primary Work-feeding mechanism comprising teed-dog, and means for imparting operative movements thereto, of an auxiliary feeding device comprising a work-engaging member, a carrier therefor, means for imparting work-advancing movements to said member, yielding means for retracting said member to an initial position, a rotary cam having a variable and a constant abutment for determining said initial position, a plurality of adjustable devices sustained by said carrier and seiective at Will for reaction With the variable and stationary abutments of said cam, and cam-rotating means.

Si in a evcing machine, the combination with prii 'y york-feeding mechanism compris' teed-dog, and means for imparting operative movements thereto, of an ants" iliary feeding device comprising a Workengaging member, a carrier therefor, means for imparting Work-advancing movements to said member, yielding means for retracting said member to an initial position, a rotary cam having a variable and a constant abutment ior determining said initial position, a plurality of adjustable devices sustained by said carrier and selective at Will for coaction With the variable and stationary abutments of said cam, cam-rotating means, and a throw-out device for rendering said cam-rotatingmeans ineiiective.

10. In a sewing machine, the combination with primary Work-feeding mechanism comprising -a feed-dog, and means for imparting operative movements thereto, of an auxiliary feeding device comprising a Work engaging member, a carrier therefor, means for in'iparting Work-advancing movements to said carrier, yielding means for retracting said member to an initial position, a rotary cam comprising a variable abutment for said carrier to determine said initial position, and means for imparting step-by-step rotary movements to said cam including a ratchetwheel, a plurality of reciprocating pawls, yielding means urging said pawls into operative engagement with said ratchet-Wheel, means for reciprocating said paWls, and a pawl adjusting device for throwing both of said pawls into ineii eetive position.

11. In a sewing machine, the combination with primary work-feeding mechanism comi,5ee,see

prising a feed-(log, and means for imparting opei e inoreinents thereto, of an auxiliary feeding device comprising a work-engaging member, a carrier therefor, means for imparting work-advancing movements to said carrier, yielding means for retracting said member to an initial position, a rotary cam comprising a variable abutment for said carrier to determine said initial position, and means for imparting step-by-step rotary movements to said cam including a ratchetwheel, a spring-pressed pawl provided With a stop-shoulder, a disk provided with a segment-notch positioned. in the rotation of: said disk to engage said stop-shoulder to maini ain said pawl in operative engagement with said ratchet-Wheel, manually manipulated means for rotating said disk to throw said pawl into ineiiective position, and means tor reciprocating said pawl.

12. In a sewing machine, the combination with primary work-feeding mechanism comprising a feed-dog, and means for imparting operative movements thereto, of an auxiliary feeding device comprising a Work-engaging member, a carrier therefor, 11 vibratory lever positioned for engagement with said carrier to impart worn-advancing movements to said member, means for vibrating said lever, yielding means for returning said carrier to initial position after the work-advancing movements thereof, a cam comprising a variable abutment for said carrier to effect an automatically varying degree of lost n10- tion between said vibratory lever and said carrier to determine said initial position, and means for rotating said cam.

In testimony whereof, I have signed my name to this specification.

ALBERT DE VOE. 

